ABOARD THE USS CARL VINSON — U.S. officials welcomed visitors Sunday to the USS Carl Vinson, from which Osama bin Laden's body was buried at sea, but did not discuss the ultra-secretive attack that killed him, reflecting America's concern over possible retaliation.

U.S. defense officials were taking measures to ensure the security of the operatives involved in the May 2 assault on a walled fortress in Abbottabad, Pakistan, particularly the Navy SEAL team that killed the world's most wanted terrorist.

President Benigno Aquino III, accompanied by senior members of his Cabinet and military chief of staff, were flown to the massive aircraft carrier Saturday as it traveled in the South China Sea toward the Philippines, a key Asian anti-terrorism ally.

A group of journalists were invited to tour and talk to sailors aboard the 97,000-ton Carl Vinson, which anchored off Manila along with three other warships on Sunday at the start of a four-day routine port call and goodwill visit.

During the 30-minute ferry ride to the Vinson, U.S. Embassy spokeswoman Wossenyelesh Mazengia told about two dozen journalists that nobody aboard the carrier would talk about bin Laden. "No one on the Vinson is authorized to discuss any operational details that involve Osama bin Laden," Mazengia said. "I'm not trying to say you can't ask, you can."

Defense Secretary Voltaire Gazmin said Aquino and his entourage were given a tour of the warship and an exhibition of fighter jets landing and taking off from the Carl Vinson, including one flown by a Filipino-American pilot.

Aquino, at one point, sat on the cockpit of an F/A-18E Super Hornet fighter jet at a hangar bay as sailors snapped pictures. He talked and posed for souvenir pictures with many beaming Filipino-American sailors, Gazmin said.

But the one thing on everybody's mind — bin Laden's burial from the Carl Vinson just 12 days earlier — did not come up. U.S. Navy officials did not touch the sensitive subject and Aquino's group saw it fit not to ask questions, Gazmin said.

"We did not ask for a briefing because it was too sensitive," Gazmin told The Associated Press on Sunday. "It was a friendly visit and we let it stay that way."

Gazmin, a retired general, said he was impressed by the stunning U.S. commando night-time strike that got bin Laden, adding it showed the might of the American military force.

Foreign Secretary Albert del Rosario, who said it was his first time to set foot on an aircraft carrier, was impressed as war planes landed and were launched by catapults from the tarmac.

"You can feel the inherent power of these fighter jets," del Rosario said.

In impromptu remarks on the ship, Aquino reaffirmed the "historic, defense and cultural ties" between the United States and the Philippines, one of Washington's oldest and closest Asian allies, presidential spokesman Ricky Carandang said.

U.S. special forces have been training and arming Filipino soldiers battling al-Qaida-linked militants in the southern Philippines since 2003.

The Carl Vinson came from the North Arabian Sea, where it had received a U.S. SEAL team, which carried bin Laden's body after killing the long-wanted al-Qaida leader in a raid on his walled compound near a Pakistani military academy.

Pentagon officials have said that on the carrier, bin Laden's body was placed in a "weighted bag," an officer made religious remarks and the remains were put on a flat board and tipped into the sea.

Defense Secretary Robert Gates has said that during a recent meeting with members of the team that attacked bin Laden, they expressed concerns about the security of their families.

Video: Bin Laden's son newest US threat?

Timeline: A timeline of Osama bin Laden's life

Considered enemy No. 1 by the U.S., the Saudi millionaire is the perpetrator behind the Sept. 11, 2001, attacks. Click on key dates to learn more about the founder of al-Qaida, an international terror network.

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An aerial view shows the residential area of Abbottabad, Pakistan, where Osama bin Laden was found and killed by U.S. commandos.
(Asif Hassan / AFP - Getty Images)
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A general view of the town of Abbottabad, May 6. Bin Laden was living in a large house close to a military academy in this garrison town, a two-and-a-half hour-drive from the capital, Islamabad.
(Khaqan Khawer / EPA)
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Supporters of Pakistani religious party Jamaat-e-Islami rally to condemn the killing of bin Laden, in Abbottabad on May 6.
(Aqeel Ahmed / AP)
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A Pakistani woman photographs her daughter on May , at a gate of the compound where bin Laden was caught and killed.
(Aqeel Ahmed / AP)
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School girls pass by armed Pakistani policemen guarding the sealed entrance to the compound in Abbottabad, May 5, in which bin Laden had been living.
(MD Nadeem / EPA)
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A Pakistani police officer gestures at a checkpoint along a road leading to a house where bin Laden was captured and killed in Abbottabad. Area residents were still confused and suspicious about bin Laden's death, which took place before dawn on Monday.
(Anjum Naveed / AP)
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Part of a damaged U.S. MH-60 helicopter lies the compound. The helicopter was destroyed by U.S. forces after a mechanical failure left it unable to take off.
(Reuters)
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A still image from video obtained by ABC News shows blood stains in the interior of the house where bin Laden was killed.
(ABC News via Reuters)
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Aerial views released by the Department of Defense show the area in Abbottabad in 2004, left, before the house was built, and in 2011, right.
(Department of Defense via Reuters)
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Boys collect pieces of metal from a wheat field outside bin Laden's house, seen in the background, on May 3. People showed off small parts of what appeared to be a U.S. helicopter that the U.S. says malfunctioned and was blown up by the American team as it retreated.
(Anjum Naveed / AP)
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An image from video seized from the walled compound of al-Qaida leader Osama bin Laden in Abbottabad, and released by the U.S. Department of Defense, shows Osama bin Laden watching TV. He is said to have spent his last weeks in a house divided, amid wives riven by suspicions. On the top floor, sharing his bedroom, was his youngest wife and favorite. The trouble came when his eldest wife showed up and moved into the bedroom on the floor below.
(Department of Defense via AP)
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Editor's note:
This image contains graphic content that some viewers may find disturbing.